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KNX TUTOR SEMINAR

                  6  KNX Easy Installation Principles


                  6.1  General

                  ETS is the best known and by far most used way to design and program a KNX
                  installation. This is called System Mode (S-Mode). KNX also offers alternatives: KNX
                  devices can also be configured without ETS. This is called Easy Mode (E-Mode) and the
                  devices are E-Mode devices. There exist three submodes: Controller Mode (Ctrl-Mode),
                  Push Button Mode (PB-Mode) and Logical Tag Extended Mode (LTE-Mode).


                  6.2  E-Mode channels

                  KNX guarantees the compatibility and runtime Interworking independently of the
                  configuration mode by fixing elementary functions in so-called Functional Blocks. These
                  specify the behaviour and coding (Datapoint Types), but still allow for a certain freedom.
                  LTE-Mode even directly bases on Functional Blocks for the description, linking and
                  communication between its devices.
                  Ctrl-Mode and PB-Mode however base their description and linking on a standard
                  selection of Datapoints and Parameters of one or more Functional Blocks. These are
                  called E-Mode Channels. Every Group Object additionally gets one of more identifiers that
                  specify its functionality (e.g. switch, time, temperature). These are called Connection
                  Codes. During the configuration, Group Objects with the same Connection Code can be
                  linked.


                  6.2.1  Ctrl-Mode
                  In Ctrl-Mode, one single, central controller takes over the role of ETS. This controller
                  assigns a unique Individual Address to each E-Mode device that it finds. A free Individual
                  Address is searched in the same way as ETS checks whether an Individual Address is
                  occupied or not. Next, of all devices, the device capabilities (E-Mode Channels and
                  parameters) are read out and shown on the display, so that the installer can select the
                  functionality and can indicate which channels should be linked. The controller decides on
                  the Group Addresses and parameter values and downloads the devices, again much in a
                  way as done by ETS, as shown in the underneath figure.



























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